rose curve
r = a * cos/sin (n theta)
n >1
if n is odd, then number of petals = n
if n is even, then number of petals = 2n
limacon curve inner loop
r = a±b cos/sin(theta)
a/b <1
limacon curve (cardoid)
r = a±b cos/sin(theta)
a/b = 1
limacon curve dimpled
r = a±b cos/sin(theta)
1 < a/b < 2
limacon curve convex
r = a±b cos/sin(theta)
a/b >= 2
spiral
r= a* theta
lemniscate curve
r^2 = a^2 sin/cos (2 theta)